Downhole Mechanism

ABSTRACT

In one aspect of the invention, a downhole tool string component comprises a fluid passageway formed between a first and second end. A valve mechanism is disposed within the fluid passageway adapted to substantially cyclically build-up and release pressure within the fluid passageway such that a pressure build-up results in radial expansion of at least a portion of the fluid passageway and wherein a pressure release results in a contraction of the portion of the fluid passageway. The valve mechanism disposed within the fluid passageway comprises a spring. Expansion and contraction of the portion of the fluid passageway varies a weight loaded to a drill bit disposed at a drilling end of the drill string.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 12/039,635, which is a continuation of U.S. patent applicationSer. No. 12/039,608, filed on Feb. 28, 2008, now U.S. Pat. No.7,762,353, which is a continuation-in-part of U.S. patent applicationSer. No. 12/037,682, filed on Feb. 26, 2008, now U.S. Pat. No.7,624,824, which is a continuation-in-part of U.S. patent applicationSer. No. 12/019,782, filed on Jan. 25, 2008, now U.S. Pat. No.7,617,886, which is a continuation-in-part of U.S. patent applicationSer. No. 11/837,321, filed on Aug. 10, 2007, now U.S. Pat. No.7,559,379, which is a continuation-in-part of U.S. patent applicationSer. No. 11/750,700, filed on May 18, 2007, now U.S. Pat. No. 7,549,489,which is a continuation-in part of U.S. patent application Ser. No.11/737,034, filed on Apr. 18, 2007, now U.S. Pat. No. 7,503,405, whichis a continuation-in-part of U.S. patent application Ser. No.11/686,638, filed on Mar. 15, 1997, now U.S. Pat. No. 7,424,922, whichis a continuation-in-part of U.S. patent application Ser. No.11/680,997, filed on Mar. 1, 2007, now U.S. Pat. No. 7,419,016, which isa continuation-in-part of U.S. patent application Ser. No. 11/673,872,filed on Feb. 12, 2007, now U.S. Pat. No. 7,484,576, which is acontinuation-in-part of U.S. patent application Ser. No. 11/611,310,filed on Dec. 15, 2006, now U.S. Pat. No. 7,600,586. This patentapplication is also a continuation-in-part of U.S. patent applicationSer. No. 11/278,935, filed on Apr. 6, 2006, now U.S. Pat. No. 7,426,968,which is a continuation-in-part of U.S. patent application Ser. No.11/277,394, filed on Mar. 24, 2006, now U.S. Pat. No. 7,398,837, whichis a continuation-in-part of U.S. patent application Ser. No.11/277,380, filed on Mar. 24, 2006, now U.S. Pat. No. 7,337,858, whichis a continuation-in-part of U.S. patent application Ser. No.11/306,976, filed on Jan. 18, 2006, now U.S. Pat. No. 7,360,610, whichis a continuation-in-part of U.S. patent application Ser. No.11/306,307, filed Dec. 22, 2005, now U.S. Pat. No. 7,225,886, which is acontinuation-in-part of U.S. patent application Ser. No. 11/306,022,filed Dec. 14, 2005, now U.S. Pat. No. 7,198,119, which is acontinuation-in-part of U.S. patent application Ser. No. 11/164,391,filed Nov. 21, 2005, now U.S. Pat. No. 7,270,196. This patentapplication is also a continuation-in-part of U.S. patent applicationSer. No. 11/555,334 which was filed on Nov. 1, 2006, now U.S. Pat. No.7,419,018. All of these applications are herein incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION

This invention relates to the field of downhole drill strings.Increasing the rate of penetration in drilling saves substantial amountof time and money in the oil and gas, geothermal, exploration, andhorizontal drilling industries.

U.S. Pat. No. 6,588,518 to Eddison, which is herein incorporated byreference for all that it contains, discloses a downhole drilling methodcomprising the production of pressure pulses in drilling fluid usingmeasurement-while-drilling (MWD) apparatus and allowing the pressurepulses to act upon a pressure responsive device to create an impulseforce on a portion of the drill string.

U.S. Pat. No. 4,890,682 to Worrall, et al., which is herein incorporatedby reference for all that it contains, discloses a jarring apparatusprovided for vibrating a pipe string in a borehole. The apparatusthereto generates at a downhole location longitudinal vibrations in thepipe string in response to flow of fluid through the interior of saidstring.

U.S. Pat. No. 4,979,577 to Walter et al., which is herein incorporatedby reference for all that it contains, discloses a flow pulsingapparatus adapted to be connected in a drill string above a drill bit.The apparatus includes a housing providing a passage for a flow ofdrilling fluid toward the bit. A valve which oscillates in the axialdirection of the drill string periodically restricts the flow throughthe passage to create pulsations in the flow and a cyclical water hammereffect thereby to vibrate the housing and the drill bit during use.Drill bit induced longitudinal vibrations in the drill string can beused to generate the oscillation of the valve along the axis of thedrill string to effect the periodic restriction of the flow or, inanother form of the invention, a special valve and spring arrangement isused to help produce the desired oscillating action and the desired flowpulsing action.

BRIEF SUMMARY OF THE INVENTION

In one aspect of the invention, a downhole tool string componentcomprises a fluid passageway formed between a first and second end. Avalve mechanism is disposed within the fluid passageway adapted tosubstantially cyclically build-up and release pressure within the fluidpassageway such that a pressure build-up results in radial expansion ofat least a portion of the fluid passageway and wherein a pressurerelease results in a contraction of the portion of the fluid passageway.The valve mechanism disposed within the fluid passageway comprises aspring. Expansion and contraction of the portion of the fluid passagewayassisting in advancing the drill string within a subterraneanenvironment. This advancing may be accomplished by varying a weightloaded to a drill bit disposed or helping to propel the drill stringalong a horizontal well.

The spring is adapted to oppose the travel of a fluid flow. The springis a tension spring or a compression spring. The spring is disposedintermediate a carrier and a centralizer and is aligned coaxially withthe downhole tool string component. The valve mechanism comprises ashaft radially supported by a bearing and the centralizer. The carrieris mounted to the shaft. The centralizer is adapted to align the shaftcoaxially with the downhole tool string component. The bearing isdisposed intermediate the shaft and the centralizer. The carriercomprises at least one port. The carrier comprises a first channelformed on a peripheral edge substantially parallel with an axis of thetool string component.

The drilling fluid is adapted to push against a fluid engaging surfacedisposed on the carrier. The valve mechanism comprises an insertdisposed intermediate and coaxially with the first end and the carrier.The centralizer and the insert are fixed within the fluid passageway.The insert comprises a taper adapted to concentrate the flow of thedownhole tool string fluid into the carrier. The engagement of the fluidagainst the carrier resisted by the spring of the valve mechanism causesthe first and second set of ports to align and misalign by oscillatingthe shaft. The insert further comprises a second channel on itsperipheral edge. The valve mechanism comprises a fluid by-pass. The bitis adapted to cyclically apply pressure to the formation. The drill bitcomprises a jack element with a distal end protruding from a front faceof the drill bit and substantially coaxial with the axis of rotation ofthe bit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective diagram of an embodiment of a string of downholetools suspended in a borehole.

FIG. 2 is a cross-sectional diagram of an embodiment of a downhole toolstring component.

FIG. 3 a is a cross-sectional diagram of another embodiment of adownhole tool string component.

FIG. 3 b is a cross-sectional diagram of another embodiment of adownhole tool string component.

FIG. 4 is a cross-sectional diagram of an embodiment of a downhole toolstring component with a drill bit.

FIG. 5 is a cross-sectional diagram of another embodiment of a downholetool string.

FIG. 6 is a cross-sectional diagram of another embodiment of a downholetool string.

FIG. 7 is a perspective diagram of a tubular assembly.

DETAILED DESCRIPTION

FIG. 1 is a perspective diagram of an embodiment of a string of downholetools 100 suspended by a derrick 101 in a borehole 102. A bottomholeassembly 103 may be located at the bottom of the borehole 102 and maycomprise a drill bit 104. As the drill bit 104 rotates downhole the toolstring 100 may advance farther into the earth. The drill string 100 maypenetrate soft or hard subterranean formations 105. The bottom holeassembly 103 and/or downhole components may comprise data acquisitiondevices which may gather data. The data may be sent to the surface via atransmission system to a data swivel 106. The data swivel 106 may sendthe data to the surface equipment. Further, the surface equipment maysend data and/or power to downhole tools and/or the bottom-hole assembly103. In some embodiments of the invention, no downhole telemetry systemis used.

FIG. 2 is a cross-sectional diagram of an embodiment of a downhole toolstring component 200 comprised of a first end 210 and a second end 211.The fluid passageway 201 may comprise a valve mechanism 202. The valvemechanism 202 may comprise a shaft 203 aligned coaxially with thedownhole tool string component 200 by a centralizer 218. The valvemechanism 202 may also comprise a fluid by-pass 204. The valve mechanism202 may also comprise a spring 205 adapted to oppose the travel of afluid flow. The drilling fluid may follow a path indicated by the arrows233. The spring 205 may be aligned coaxially with the downhole toolstring component 200 and may be a compression spring or a tensionspring. The valve mechanism 202 may also comprise a carrier 206comprised of ports 220 and a first channel 221. The valve mechanism 202may also comprise an insert 207 disposed coaxially with the axis of thedownhole tool string component 200. The insert 207 may comprise a set ofports 222 and a second channel 223. The insert 207 may comprise a taper208 adapted to concentrate the flow of the drilling fluid into thecarrier 206. The spring 205 may be adapted to resist the engagement ofthe fluid flow against the carrier 206. Without the fluid flow the portsmay be misaligned due to the force of the spring. Once flow is added,the misaligned ports may obstruct the flow causing a pressure build-up.As the pressure increases the force of the spring may be overcome andeventual align the ports. Once the ports are aligned, the flow may passthrough the ports relieving the pressure build-up such that the springmoves the carrier to misalign the ports. This cycle of aligning andmisaligning the carrier ports 220 and insert ports 222 aids in theadvancing the drill string within its subterranean environments. As bothsets of ports 220, 222 are misaligned, the pressure build up from thedrilling fluid may cause the wall 230 of the downhole drill stringcomponent 200 to expand. As both sets of ports 220, 222 are aligned, thepressure build up from the drilling fluid may be released as thedrilling fluid is allowed to flow from the first channel 221, throughthe ports 220, 222 and into the second channel 223. The shaft 203 andcarrier 206 may be secured to each other by means of press-fitting theshaft 203 into the carrier 206 or shrink fitting the carrier 206 overthe shaft 203. The shaft 203 may be allowed to move axially by a bearing235 disposed intermediate the centralizer 218 and shaft 203.

FIG. 3 a shows a cross-sectional diagram of another embodiment of adownhole tool string component 200. With the ports 220 on the carrier206 misaligned in relation to the ports 222 on the insert 207, thedrilling fluid is allowed to build up within the fluid passageway 201causing the walls 230 of the downhole drill string component 200 toexpand radially outward.

FIG. 3 b shows a cross-sectional diagram of another embodiment of adownhole tool string component 200. With the ports 220 on the carrier206 aligned with the ports 222 on the insert 207, the drilling fluid isallowed to pass from the first end 210 to the second end 211 (shown inFIG. 2), thus releasing the build up of pressure within the fluidpassageway 201 and allowing the walls 230 of the downhole drill stringcomponent 200 to contract. As the pipe radially contracts, the pipe isbelieved to expand axially. This axial expansion is believed to increasethe weight loaded to the drill bit and transfer a pressure wave into theformation. In some embodiments, the pressure relief above the valve willincrease the pressure below the valve thereby pushing against the drillbit, further increasing the weight loaded to the drill bit. Also in someembodiments the affect of the oscillating valve's mass will fluctuatethe weight loaded to the drill bit.

FIG. 4 shows a cross-sectional diagram of a downhole drill stringcomponent 200 with a drill bit 340. The drill bit 340 may be made in twoportions. The first portion 305 may comprise at least the shank 300 anda part of the bit body 301. The second portion 310 may comprise theworking face 302 and at least another part of the bit body 301. The twoportions 305, 310 may be welded together or otherwise joined together ata joint 315.

FIG. 5 shows a perspective diagram of another embodiment of a downholetool string component 200. In this embodiment, the downhole tool stringcomponent 200 may comprise a valve mechanism 202. The valve mechanism202 may comprise a carrier 206 which may be comprised of at least onehole 405 disposed on the carrier 206. The at least one hole 405 may bedisposed offset at least one port 410 disposed on a guide 411 such thatdrilling fluid is unable to pass from the first end 210 to second end211 if the carrier 206 is against the guide 411. The drilling fluid mayfollow the path indicated by the arrow 233. The guide 411 may be securedto the walls 230 of the downhole drill string component 200 and mayserve to align the shaft 203 axially with the downhole drill stringcomponent 200. A bearing 235 may be disposed intermediate the carrier206 and the wall 230 of the downhole drill string component 200. Thevalve mechanism 202 may also comprise an insert 207 disposedintermediate the wall 230 of the downhole drill string component 200 andthe shaft 203. A spring 205 may be disposed intermediate the insert 207and the carrier 206 and coaxially with the downhole drill stringcomponent 200.

FIG. 6 shows a perspective diagram of another embodiment of a downholetool string component 200. In this embodiment, the valve mechanism 202may comprise a spring 205 disposed intermediate a carrier 206 and insert207 and coaxially with the downhole tool string component 200. Theinsert 207 may comprise a set of ports 610 and a bearing 612 disposedintermediate a shaft 203 and the insert 207. The drilling fluid mayfollow the path indicated by the arrow 233.

FIG. 7 is a perspective diagram of a tubular assembly 2000 penetratinginto a subterranean environment 2001. Preferable the tubular assembly200 is a drill string 100 which comprises a bore for the passingdrilling mud through. The tubular assembly may comprise a mechanism forcontracting and expanding a diameter of the tubular assembly such that awave is generated which travels of the tubular assembly. This mechanismmay be a valve mechanism such as the valve mechanism described in FIG.2. In horizontal drilling applications the length 2003 of the tubularassembly may be engaged with the bore wall and waves 2002 may aid inmoving the tubular assembly in its desired trajectory. In someembodiments of the present invention, the tubular assembly is notrotated such as in traditionally oil and gas exploration, but ispropelling along its trajectory through the waves 2002.

The tubular assembly may be used in oil and gas drilling, geothermaloperations, exploration, and horizontal drilling such as for utilitylines, coal methane, natural gas, and shallow oil and gas.

In one aspect of the present invention a method for penetrating asubterranean environment includes the steps of providing a tubularassembly with a oscillating valve mechanism disposed within its bore,the valve mechanism comprising the characteristic such that as a fluidis passing through the valve, the valve will oscillate between an openand closed position; generating a wave along a length of the tubularassembly by radially expanding and contracting the tubular assembly byincreasing and decreasing a fluid pressure by oscillating the valvemechanism; and engaging the length the tubular assembly such that thewave moves the tubular assembly along a trajectory.

In another aspect of the present invention a method for penetrating asubterranean environment comprises the steps of providing a tubularassembly with a mechanism disposed within its bore adapted to expand andcontract a diameter of the tubular assembly; generating a wave along alength of the tubular assembly by radially expanding and contracting adiameter of the tubular assembly; and engaging the length the tubularassembly such that the wave moves the tubular assembly along atrajectory.

Whereas the present invention has been described in particular relationto the drawings attached hereto, it should be understood that other andfurther modifications apart from those shown or suggested herein, may bemade within the scope and spirit of the present invention.

1. A method for penetrating a subterranean environment, comprising thesteps of: providing a tubular assembly with a oscillating valvemechanism disposed within its bore, the valve mechanism comprising thecharacteristic such that as a fluid is passing through the valve, thevalve will oscillate between an open and closed position; generating awave along a length of the tubular assembly by radially expanding andcontracting the tubular assembly by increasing and decreasing a fluidpressure by oscillating the valve mechanism; and engaging the length thetubular assembly such that the wave moves the tubular assembly along atrajectory.
 2. The method of claim 1, wherein the tubular assembly is adrill string.
 3. The method of claim 2, wherein the drill stringcomprises a drill bit with a shaft protruding out of its working face.4. The method of claim 3, wherein the shaft is part of the valvemechanisms.
 5. The method of claim 1, wherein the tubular assemblycomprises multiple valve mechanism.
 6. The method of claim 1, whereinthe tubular assembly secretes a lubricant.
 7. The method of claim 1,wherein the step of engaging the length of the tubular assembly isaccomplished by drilling a substantially horizontal well.
 8. The methodof claim 1, wherein the fluid is drilling mud.
 9. The method of claim 1,wherein the valve mechanism comprises a spring adapted to resist a fluidflow passing through the bore.
 10. The method of claim 9, wherein thespring forces the valve shut and generates a pressure build-up until thepressure is high enough to open the valve.
 11. The method of claim 1,wherein the valve mechanism comprises multiple ports.
 12. The method ofclaim 1, wherein the valve mechanism comprises an upper and lowerbearing to support a shaft.
 13. The method of claim 12, wherein theshaft is substantially coaxial with the tubular assembly.
 14. A methodfor penetrating a subterranean environment, comprising the steps of:providing a tubular assembly with a mechanism disposed within its boreadapted to expand and contract a diameter of the tubular assembly;generating a wave along a length of the tubular assembly by radiallyexpanding and contracting a diameter of the tubular assembly; andengaging the length the tubular assembly such that the wave moves thetubular assembly along a trajectory.
 15. The method of claim 14, whereinthe tubular assembly is a drill string.
 16. The method of claim 15,wherein the drill string comprises a drill bit with a shaft protrudingout of its working face.
 17. The method of claim 16, wherein the shaftis part of the valve mechanism.
 18. The method of claim 14, wherein thetubular assembly comprises multiple mechanisms.
 19. The method of claim14, wherein the tubular assembly secretes a lubricant.
 20. The method ofclaim 14, wherein the step of engaging the length of the tubularassembly is accomplished by drilling a substantially horizontal well.